From: "Darrick J. Wong" Subject: [PATCH 26/31] libext2fs: openfs() musn't allow bigalloc without EXT2_FLAGS_64BITS Date: Mon, 30 Sep 2013 18:29:28 -0700 Message-ID: <20131001012928.28415.62086.stgit@birch.djwong.org> References: <20131001012642.28415.89353.stgit@birch.djwong.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: linux-ext4@vger.kernel.org To: tytso@mit.edu, darrick.wong@oracle.com Return-path: Received: from aserp1040.oracle.com ([141.146.126.69]:22942 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755175Ab3JAB3i (ORCPT ); Mon, 30 Sep 2013 21:29:38 -0400 In-Reply-To: <20131001012642.28415.89353.stgit@birch.djwong.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: Currently, only the 64-bit bitmap implementation supports the block<->cluster conversions that bigalloc requires. Therefore, if we have a bigalloc filesystem, require EXT2_FLAGS_64BITS be passed in to ext2fs_open(). Signed-off-by: Darrick J. Wong --- lib/ext2fs/openfs.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c index 3c0bf14..f486a35 100644 --- a/lib/ext2fs/openfs.c +++ b/lib/ext2fs/openfs.c @@ -272,6 +272,18 @@ errcode_t ext2fs_open3(const char *name, const char *io_options, retval = EXT2_ET_CORRUPT_SUPERBLOCK; goto cleanup; } + + /* + * bigalloc requires cluster-aware bitfield operations, which at the + * moment means we need EXT2_FLAG_64BITS. + */ + if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, + EXT4_FEATURE_RO_COMPAT_BIGALLOC) && + !(flags & EXT2_FLAG_64BITS)) { + retval = EXT2_ET_CANT_USE_LEGACY_BITMAPS; + goto cleanup; + } + if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super, EXT4_FEATURE_RO_COMPAT_BIGALLOC) && (fs->super->s_log_block_size != fs->super->s_log_cluster_size)) {