From: djwong Subject: Re: [dm-devel] EXT4-fs error (device dm-42): ext4_mb_generate_buddy:741: group 1904, 32254 clusters in bitmap, 32258 in gd Date: Thu, 7 Jun 2012 15:27:29 -0700 Message-ID: <20120607222729.GI6938@tux1.beaverton.ibm.com> References: <471046920.20120604234941@eikelenboom.it> <20120605000356.GM29466@outflux.net> <1018371644.20120605224154@eikelenboom.it> <20120605210806.GB7182@thunk.org> <1883708187.20120606090126@eikelenboom.it> <1482118647.20120606164012@eikelenboom.it> <20120607042756.GA30776@thunk.org> Reply-To: djwong@us.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: "Ted Ts'o" , Sander Eikelenboom , Kees Cook , Linus Torvalds , dm-devel@redhat.com, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: Content-Disposition: inline In-Reply-To: <20120607042756.GA30776@thunk.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Thu, Jun 07, 2012 at 12:27:56AM -0400, Ted Ts'o wrote: > I think this patch should fix things. Could you give it a try (after > re-enabling uninit_bg and then running e2fsck on the file systems)? > > Many thanks, > > - Ted > > commit b6b218940d47f20fc14e4d203930c575be0c65bf > Author: Theodore Ts'o > Date: Thu Jun 7 00:26:56 2012 -0400 > > ext4: fix the free blocks calculation for ext3 file systems w/ uninit_bg > > Ext3 filesystems that are converted to use as many ext4 file systems > as possible Just to clarify the description a bit: Did you mean "..as many ext4 filesystem _features_ as possible" ? > will enable uninit_bg to speed up e2fsck times. File > systems with an native ext3 layout of inode tables and block Perhaps "On file systems with a native ext3 layout..." ? --D > allocation bitmaps (as opposed to ext4's flex_bg layout), ext4 would > sometimes incorrectly calculate the number of free blocks in an > uninitialized block group. As a result, when first allocating a block > in block group marked uninitalized, ext4 would incorrectly report that > the file system was corrupt: > > EXT4-fs error (device dm-42): ext4_mb_generate_buddy:741: group 1699, 32254 clusters in bitmap, 32258 in gd > > Fix the calculation in ext4_num_overhead_clusters() to avoid this > problem. > > Signed-off-by: "Theodore Ts'o" > > diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c > index 99b6324..cee7812 100644 > --- a/fs/ext4/balloc.c > +++ b/fs/ext4/balloc.c > @@ -90,8 +90,8 @@ unsigned ext4_num_overhead_clusters(struct super_block *sb, > * unusual file system layouts. > */ > if (ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), block_group)) { > - block_cluster = EXT4_B2C(sbi, (start - > - ext4_block_bitmap(sb, gdp))); > + block_cluster = EXT4_B2C(sbi, > + ext4_block_bitmap(sb, gdp) - start); > if (block_cluster < num_clusters) > block_cluster = -1; > else if (block_cluster == num_clusters) { > @@ -102,7 +102,7 @@ unsigned ext4_num_overhead_clusters(struct super_block *sb, > > if (ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), block_group)) { > inode_cluster = EXT4_B2C(sbi, > - start - ext4_inode_bitmap(sb, gdp)); > + ext4_inode_bitmap(sb, gdp) - start); > if (inode_cluster < num_clusters) > inode_cluster = -1; > else if (inode_cluster == num_clusters) { > @@ -114,7 +114,7 @@ unsigned ext4_num_overhead_clusters(struct super_block *sb, > itbl_blk = ext4_inode_table(sb, gdp); > for (i = 0; i < sbi->s_itb_per_group; i++) { > if (ext4_block_in_group(sb, itbl_blk + i, block_group)) { > - c = EXT4_B2C(sbi, start - itbl_blk + i); > + c = EXT4_B2C(sbi, itbl_blk + i - start); > if ((c < num_clusters) || (c == inode_cluster) || > (c == block_cluster) || (c == itbl_cluster)) > continue; > > -- > dm-devel mailing list > dm-devel@redhat.com > https://www.redhat.com/mailman/listinfo/dm-devel >