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 960FDC4332F for ; Sat, 31 Dec 2022 02:09:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236164AbiLaCJG (ORCPT ); Fri, 30 Dec 2022 21:09:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231494AbiLaCJG (ORCPT ); Fri, 30 Dec 2022 21:09:06 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0930F140F1 for ; Fri, 30 Dec 2022 18:09:05 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id BB1CCB81E00 for ; Sat, 31 Dec 2022 02:09:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 83393C433EF; Sat, 31 Dec 2022 02:09:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1672452542; bh=0aHUHx5/xkOnN4tnRVs+IxrB4grTH3jRhmKoLekqeOo=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=pG3wU+ETE3yJzqgkITO40sZ65ynzaH/CzKWuREJ8tQ5WA27CZJa0TNLNVH0j5h6Ae JcXeb365iy2iAaavcDD98A5cWzsXaAufQl9GhzY++BwDfhEYi/f96AUBan4caPQPSO MQADZhHtyaQkwH7A6CM4qgqkKgY8uOIWfaNjc6Wonu7iuR7FgZhJIublcSGCZLD2na 3CFdjMZ9p2iVrWF/4nRCV1Zn66GYfCUc4EtHKSFs3TXx1rXMK2gI1dMws1QUN1BTSi D5KZUNn8eorHZHHLz38/GI9E0ewD+91mR/KWjdqcA9W76r40hv/C8EjDJ6IeVNbj34 8pXGPKYTfKXng== Subject: [PATCH 23/26] xfs: create libxfs helper to rename two directory entries From: "Darrick J. Wong" To: djwong@kernel.org, cem@kernel.org Cc: linux-xfs@vger.kernel.org Date: Fri, 30 Dec 2022 14:19:15 -0800 Message-ID: <167243875592.723621.16095946193604750197.stgit@magnolia> In-Reply-To: <167243875315.723621.17759760420120912799.stgit@magnolia> References: <167243875315.723621.17759760420120912799.stgit@magnolia> User-Agent: StGit/0.19 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org From: Darrick J. Wong Create a new libxfs function to rename two directory entries. The upcoming metadata directory feature will need this to replace a metadata inode directory entry. Signed-off-by: Darrick J. Wong --- libxfs/xfs_dir2.c | 203 +++++++++++++++++++++++++++++++++++++++++++++++++++++ libxfs/xfs_dir2.h | 5 + 2 files changed, 208 insertions(+) diff --git a/libxfs/xfs_dir2.c b/libxfs/xfs_dir2.c index b0bb22ac506..ae91fc48d79 100644 --- a/libxfs/xfs_dir2.c +++ b/libxfs/xfs_dir2.c @@ -22,6 +22,7 @@ #include "xfs_bmap_btree.h" #include "xfs_trans_space.h" #include "xfs_ag.h" +#include "xfs_ialloc.h" const struct xfs_name xfs_name_dotdot = { .name = (const unsigned char *)"..", @@ -1057,3 +1058,205 @@ xfs_dir_exchange( return 0; } + +/* + * Given an entry (@src_name, @src_ip) in directory @src_dp, make the entry + * @target_name in directory @target_dp point to @src_ip and remove the + * original entry, cleaning up everything left behind. + * + * Cleanup involves dropping a link count on @target_ip, and either removing + * the (@src_name, @src_ip) entry from @src_dp or simply replacing the entry + * with (@src_name, @wip) if a whiteout inode @wip is supplied. + * + * All inodes must have the ILOCK held. We assume that if @src_ip is a + * directory then its '..' doesn't already point to @target_dp, and that @wip + * is a freshly allocated whiteout. + */ +int +xfs_dir_rename( + struct xfs_trans *tp, + struct xfs_inode *src_dp, + struct xfs_name *src_name, + struct xfs_inode *src_ip, + struct xfs_inode *target_dp, + struct xfs_name *target_name, + struct xfs_inode *target_ip, + unsigned int spaceres, + struct xfs_inode *wip) +{ + struct xfs_mount *mp = tp->t_mountp; + bool new_parent = (src_dp != target_dp); + bool src_is_directory; + int error; + + src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode); + + /* + * Check for expected errors before we dirty the transaction + * so we can return an error without a transaction abort. + */ + if (target_ip == NULL) { + /* + * If there's no space reservation, check the entry will + * fit before actually inserting it. + */ + if (!spaceres) { + error = xfs_dir_canenter(tp, target_dp, target_name); + if (error) + return error; + } + } else { + /* + * If target exists and it's a directory, check that whether + * it can be destroyed. + */ + if (S_ISDIR(VFS_I(target_ip)->i_mode) && + (!xfs_dir_isempty(target_ip) || + (VFS_I(target_ip)->i_nlink > 2))) + return -EEXIST; + } + + /* + * Directory entry creation below may acquire the AGF. Remove + * the whiteout from the unlinked list first to preserve correct + * AGI/AGF locking order. This dirties the transaction so failures + * after this point will abort and log recovery will clean up the + * mess. + * + * For whiteouts, we need to bump the link count on the whiteout + * inode. After this point, we have a real link, clear the tmpfile + * state flag from the inode so it doesn't accidentally get misused + * in future. + */ + if (wip) { + struct xfs_perag *pag; + + ASSERT(VFS_I(wip)->i_nlink == 0); + + pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, wip->i_ino)); + error = xfs_iunlink_remove(tp, pag, wip); + xfs_perag_put(pag); + if (error) + return error; + + xfs_bumplink(tp, wip); + } + + /* + * Set up the target. + */ + if (target_ip == NULL) { + /* + * If target does not exist and the rename crosses + * directories, adjust the target directory link count + * to account for the ".." reference from the new entry. + */ + error = xfs_dir_createname(tp, target_dp, target_name, + src_ip->i_ino, spaceres); + if (error) + return error; + + xfs_trans_ichgtime(tp, target_dp, + XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + + if (new_parent && src_is_directory) { + xfs_bumplink(tp, target_dp); + } + } else { /* target_ip != NULL */ + /* + * Link the source inode under the target name. + * If the source inode is a directory and we are moving + * it across directories, its ".." entry will be + * inconsistent until we replace that down below. + * + * In case there is already an entry with the same + * name at the destination directory, remove it first. + */ + error = xfs_dir_replace(tp, target_dp, target_name, + src_ip->i_ino, spaceres); + if (error) + return error; + + xfs_trans_ichgtime(tp, target_dp, + XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + + /* + * Decrement the link count on the target since the target + * dir no longer points to it. + */ + error = xfs_droplink(tp, target_ip); + if (error) + return error; + + if (src_is_directory) { + /* + * Drop the link from the old "." entry. + */ + error = xfs_droplink(tp, target_ip); + if (error) + return error; + } + } /* target_ip != NULL */ + + /* + * Remove the source. + */ + if (new_parent && src_is_directory) { + /* + * Rewrite the ".." entry to point to the new + * directory. + */ + error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot, + target_dp->i_ino, spaceres); + ASSERT(error != -EEXIST); + if (error) + return error; + } + + /* + * We always want to hit the ctime on the source inode. + * + * This isn't strictly required by the standards since the source + * inode isn't really being changed, but old unix file systems did + * it and some incremental backup programs won't work without it. + */ + xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG); + xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE); + + /* + * Adjust the link count on src_dp. This is necessary when + * renaming a directory, either within one parent when + * the target existed, or across two parent directories. + */ + if (src_is_directory && (new_parent || target_ip != NULL)) { + + /* + * Decrement link count on src_directory since the + * entry that's moved no longer points to it. + */ + error = xfs_droplink(tp, src_dp); + if (error) + return error; + } + + /* + * For whiteouts, we only need to update the source dirent with the + * inode number of the whiteout inode rather than removing it + * altogether. + */ + if (wip) + error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino, + spaceres); + else + error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino, + spaceres); + if (error) + return error; + + xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE); + if (new_parent) + xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE); + + return 0; +} diff --git a/libxfs/xfs_dir2.h b/libxfs/xfs_dir2.h index f63390236f0..00b4642bc8a 100644 --- a/libxfs/xfs_dir2.h +++ b/libxfs/xfs_dir2.h @@ -266,5 +266,10 @@ int xfs_dir_exchange(struct xfs_trans *tp, struct xfs_inode *dp1, struct xfs_name *name1, struct xfs_inode *ip1, struct xfs_inode *dp2, struct xfs_name *name2, struct xfs_inode *ip2, unsigned int spaceres); +int xfs_dir_rename(struct xfs_trans *tp, struct xfs_inode *src_dp, + struct xfs_name *src_name, struct xfs_inode *src_ip, + struct xfs_inode *target_dp, struct xfs_name *target_name, + struct xfs_inode *target_ip, unsigned int spaceres, + struct xfs_inode *wip); #endif /* __XFS_DIR2_H__ */