From patchwork Wed Mar 9 19:22:47 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 12775518 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 0AEF3C433EF for ; Wed, 9 Mar 2022 19:23:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237839AbiCITY1 (ORCPT ); Wed, 9 Mar 2022 14:24:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46964 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237886AbiCITYF (ORCPT ); Wed, 9 Mar 2022 14:24:05 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D81F6140B9 for ; Wed, 9 Mar 2022 11:22:48 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 604DC61904 for ; Wed, 9 Mar 2022 19:22:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C25DCC340E8; Wed, 9 Mar 2022 19:22:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646853767; bh=HkUeI+4DI364thBKHvUNFPausuSekm9sktGG29TzGKU=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=XZNveaXVA8qPFUYy/cHBmt/oh5TqUP/kQZRgwOqqS7JlvgtQ4A72AFnyo/k3PMIZx pF/Lruwfjc7In2hBG8L/rOiOZRXSz1J842avX9YuMTIlNtgYbKaxK2mfJjIxicHjAT aWEddYOCf90hsGQ8ZQgi1XDv6J2OgzRw31uFcVbtrFgmmKw9ytFqj8NRM5lnhX4aZ+ abVhbb5sKTEgtOe7u2DTOkUmWokt9gfMlJ+iUUhoMgrDmSsRKwdOqhfQEmIspz591b IbnJCevNVg0hROKefrJVZ8H34h5NcuFbL8iZL0EZ3rEb+0U/dIwLJZG09ADMPCFgyY KUQZbQj6Wjzsg== Subject: [PATCH 2/2] xfs: constify xfs_name_dotdot From: "Darrick J. Wong" To: djwong@kernel.org Cc: linux-xfs@vger.kernel.org Date: Wed, 09 Mar 2022 11:22:47 -0800 Message-ID: <164685376731.496011.1567771444928519597.stgit@magnolia> In-Reply-To: <164685375609.496011.2754821878646256374.stgit@magnolia> References: <164685375609.496011.2754821878646256374.stgit@magnolia> User-Agent: StGit/0.19 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org From: Darrick J. Wong The symbol xfs_name_dotdot is a global variable that the xfs codebase uses here and there to look up directory dotdot entries. Currently it's a non-const variable, which means that it's a mutable global variable. So far nobody's abused this to cause problems, but let's use the compiler to enforce that. Signed-off-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_dir2.c | 6 +++++- fs/xfs/libxfs/xfs_dir2.h | 2 +- fs/xfs/scrub/parent.c | 6 ++++-- fs/xfs/xfs_export.c | 3 ++- 4 files changed, 12 insertions(+), 5 deletions(-) diff --git a/fs/xfs/libxfs/xfs_dir2.c b/fs/xfs/libxfs/xfs_dir2.c index a77d931d65a3..cf9fa07e62d5 100644 --- a/fs/xfs/libxfs/xfs_dir2.c +++ b/fs/xfs/libxfs/xfs_dir2.c @@ -19,7 +19,11 @@ #include "xfs_error.h" #include "xfs_trace.h" -struct xfs_name xfs_name_dotdot = { (unsigned char *)"..", 2, XFS_DIR3_FT_DIR }; +const struct xfs_name xfs_name_dotdot = { + .name = (unsigned char *)"..", + .len = 2, + .type = XFS_DIR3_FT_DIR, +}; /* * Convert inode mode to directory entry filetype diff --git a/fs/xfs/libxfs/xfs_dir2.h b/fs/xfs/libxfs/xfs_dir2.h index f7e6cc869c13..3120d1da9d68 100644 --- a/fs/xfs/libxfs/xfs_dir2.h +++ b/fs/xfs/libxfs/xfs_dir2.h @@ -21,7 +21,7 @@ struct xfs_dir2_data_unused; struct xfs_dir3_icfree_hdr; struct xfs_dir3_icleaf_hdr; -extern struct xfs_name xfs_name_dotdot; +extern const struct xfs_name xfs_name_dotdot; /* * Convert inode mode to directory entry filetype diff --git a/fs/xfs/scrub/parent.c b/fs/xfs/scrub/parent.c index ab182a5cd0c0..e9549d998cdc 100644 --- a/fs/xfs/scrub/parent.c +++ b/fs/xfs/scrub/parent.c @@ -131,6 +131,7 @@ xchk_parent_validate( xfs_ino_t dnum, bool *try_again) { + struct xfs_name dotdot = xfs_name_dotdot; struct xfs_mount *mp = sc->mp; struct xfs_inode *dp = NULL; xfs_nlink_t expected_nlink; @@ -230,7 +231,7 @@ xchk_parent_validate( expected_nlink = VFS_I(sc->ip)->i_nlink == 0 ? 0 : 1; /* Look up '..' to see if the inode changed. */ - error = xfs_dir_lookup(sc->tp, sc->ip, &xfs_name_dotdot, &dnum, NULL); + error = xfs_dir_lookup(sc->tp, sc->ip, &dotdot, &dnum, NULL); if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error)) goto out_rele; @@ -263,6 +264,7 @@ int xchk_parent( struct xfs_scrub *sc) { + struct xfs_name dotdot = xfs_name_dotdot; struct xfs_mount *mp = sc->mp; xfs_ino_t dnum; bool try_again; @@ -293,7 +295,7 @@ xchk_parent( xfs_iunlock(sc->ip, XFS_ILOCK_EXCL | XFS_MMAPLOCK_EXCL); /* Look up '..' */ - error = xfs_dir_lookup(sc->tp, sc->ip, &xfs_name_dotdot, &dnum, NULL); + error = xfs_dir_lookup(sc->tp, sc->ip, &dotdot, &dnum, NULL); if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error)) goto out; if (!xfs_verify_dir_ino(mp, dnum)) { diff --git a/fs/xfs/xfs_export.c b/fs/xfs/xfs_export.c index 1064c2342876..8939119191f4 100644 --- a/fs/xfs/xfs_export.c +++ b/fs/xfs/xfs_export.c @@ -206,10 +206,11 @@ STATIC struct dentry * xfs_fs_get_parent( struct dentry *child) { + struct xfs_name dotdot = xfs_name_dotdot; int error; struct xfs_inode *cip; - error = xfs_lookup(XFS_I(d_inode(child)), &xfs_name_dotdot, &cip, NULL); + error = xfs_lookup(XFS_I(d_inode(child)), &dotdot, &cip, NULL); if (unlikely(error)) return ERR_PTR(error);