From: Peter Staubach Subject: Re: [PATCH 1/5] ext4: unlock group before ext4_error Date: Thu, 20 Nov 2008 13:35:11 -0500 Message-ID: <4925ADDF.10103@redhat.com> References: <1227205580-27596-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: cmm@us.ibm.com, tytso@mit.edu, sandeen@redhat.com, linux-ext4@vger.kernel.org To: "Aneesh Kumar K.V" Return-path: Received: from mx2.redhat.com ([66.187.237.31]:38020 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753735AbYKTSfg (ORCPT ); Thu, 20 Nov 2008 13:35:36 -0500 In-Reply-To: <1227205580-27596-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Aneesh Kumar K.V wrote: > Otherwise ext4_error will cause BUG because of > scheduling in atomic context. > > Signed-off-by: Aneesh Kumar K.V > --- > fs/ext4/mballoc.c | 12 ++++++++++++ > 1 files changed, 12 insertions(+), 0 deletions(-) > > diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c > index 772e05b..039a5a6 100644 > --- a/fs/ext4/mballoc.c > +++ b/fs/ext4/mballoc.c > @@ -460,10 +460,12 @@ static void mb_free_blocks_double(struct inode *inode, struct ext4_buddy *e4b, > blocknr += > le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block); > > + ext4_unlock_group(sb, e4b->bd_group); > ext4_error(sb, __func__, "double-free of inode" > " %lu's block %llu(bit %u in group %u)\n", > inode ? inode->i_ino : 0, blocknr, > first + i, e4b->bd_group); > + ext4_unlock_group(sb, e4b->bd_group); > This should be ext4_lock_group(sb, e4b->bd_group); shouldn't it? Thanx... ps > } > mb_clear_bit(first + i, e4b->bd_info->bb_bitmap); > } > @@ -704,6 +706,7 @@ static void ext4_mb_generate_buddy(struct super_block *sb, > grp->bb_fragments = fragments; > > if (free != grp->bb_free) { > + ext4_unlock_group(sb, group); > ext4_error(sb, __func__, > "EXT4-fs: group %u: %u blocks in bitmap, %u in gd\n", > group, free, grp->bb_free); > @@ -711,6 +714,7 @@ static void ext4_mb_generate_buddy(struct super_block *sb, > * If we intent to continue, we consider group descritor > * corrupt and update bb_free using bitmap value > */ > + ext4_lock_group(sb, group); > grp->bb_free = free; > } > > @@ -1625,15 +1629,18 @@ static void ext4_mb_complex_scan_group(struct ext4_allocation_context *ac, > * free blocks even though group info says we > * we have free blocks > */ > + ext4_unlock_group(sb, e4b->bd_group); > ext4_error(sb, __func__, "%d free blocks as per " > "group info. But bitmap says 0\n", > free); > + ext4_lock_group(sb, e4b->bd_group); > break; > } > > mb_find_extent(e4b, 0, i, ac->ac_g_ex.fe_len, &ex); > BUG_ON(ex.fe_len <= 0); > if (free < ex.fe_len) { > + ext4_unlock_group(sb, e4b->bd_group); > ext4_error(sb, __func__, "%d free blocks as per " > "group info. But got %d blocks\n", > free, ex.fe_len); > @@ -1642,6 +1649,7 @@ static void ext4_mb_complex_scan_group(struct ext4_allocation_context *ac, > * indicate that the bitmap is corrupt. So exit > * without claiming the space. > */ > + ext4_lock_group(sb, e4b->bd_group); > break; > } > > @@ -3789,6 +3797,7 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh, > bit = next + 1; > } > if (free != pa->pa_free) { > + ext4_unlock_group(sb, group); > printk(KERN_CRIT "pa %p: logic %lu, phys. %lu, len %lu\n", > pa, (unsigned long) pa->pa_lstart, > (unsigned long) pa->pa_pstart, > @@ -3799,6 +3808,7 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh, > * pa is already deleted so we use the value obtained > * from the bitmap and continue. > */ > + ext4_lock_group(sb, group); > } > atomic_add(free, &sbi->s_mb_discarded); > > @@ -4607,9 +4617,11 @@ ext4_mb_free_metadata(handle_t *handle, struct ext4_buddy *e4b, > else if (block >= (entry->start_blk + entry->count)) > n = &(*n)->rb_right; > else { > + ext4_unlock_group(sb, e4b->bd_group); > ext4_error(sb, __func__, > "Double free of blocks %d (%d %d)\n", > block, entry->start_blk, entry->count); > + ext4_unlock_group(sb, e4b->bd_group); > return 0; > } > } >